1. Field
This disclosure relates generally to forming a strain gauge, and more specifically, to forming a multiple layer strain gauge.
2. Related Art
Integrated circuits may be exposed to strain when the package is introduced into an environment with temperature changes, such as an integrated circuit used in a car or a computer. Extreme temperature changes may create enough strain to cause the integrated circuits to fail. Thus, manufacturers of integrated circuits want to understand how their packaged integrated circuits withstand strain in certain temperature ranges so that they can build reliable products. Hence, manufacturers often run tests to try to determine the strain the package experiences under predetermined conditions. However, measuring strain of a packaged integrated circuit is difficult. External strain gauges are used but they are large compared to the packaged integrated circuits. At best overall strain can be measured and strain at localized areas cannot be determined. Also, due to their large size, the strain gauges often do not fit into the electrical test systems used to determine product functionality. Hence, there is a need for a way to measure strain of integrated circuit packages.